It is well known in the building trades to install pipes and the like which protrude from a roof, which pipes provide ventillation, exhaust, etc. One approach to sealing the joint between a pipe and roof has been to extend roofing material, such as non-bituminous membranes of polyvinyl chloride (PVC), ethylene propylene diene monomer polymers (EPDM), Hypolon, neoprene and other rubbers, sheet lead, and bituminous membranes, etc. up the sides of the pipe and down into the pipe. Other approaches include the use of skirted cylindrical pipe sleeves which surround the pipe. These approaches heretofore have generally involved the use of lap sealants, etc. to seal the gaps between the pipe, sleeve and roof. Further, ring clamps are often employed in these arrangements to ensure a water-tight seal between the pipe and upright sleeve.